FORDA - Jurnal
ARBUSCULAR MYCORRHIZAL FUNGI INCREASED PLANT
GROWTH AND NUTRIENT CONCENTRATIONS OF MILKWOOD
TROPICAL TREE SPECIES Alstonia scholaris UNDER GREENHOUSE
CONDITIONS
Maman Turjaman1, 2, Erdy Santoso1 and Keitaro Tawaraya3
ABSTRACT
The objective of this study was to determine the effect of five arbuscular mycorrhizal (AM) fungi
on the early growth of Alstonia scholaris (milkwood) seedlings. The seedlings were inoculated with
Glomus clarum Nicholson & Schenk, Gigaspora decipiens Hall & Abbott, Glomus sp. ACA Tulasne &
Tulasne, Entrophospora sp. Ames & Scheneider, and Glomus sp. ZEA Tulasne & Tulasne, and
uninoculated (control) under greenhouse conditions. Percentage of AM colonization, plant growth,
survival rate, mycorrhizal dependency (MD), shoot nitrogen (N), phosphorus (P), potassium (K),
calcium (Ca), and magnesium (Mg) concentrations were measured after 150 days. Survival rates were
higher in the AM-colonized seedlings at 150 days after transplantation than those in the control
seedlings. Mycorrhizal Dependency (MD) values were 80, 78, 79, 78 and 78% in A. scholaris inoculated
with G. clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp., and Glomus sp. ZEA, respectively. Shoot
N, P, K, Ca and Mg content of the seedlings were increased by AM fungi as much as 82-86, 81-86, 81-86,
88-91 and 85-90%, respectively. The percentage of AM colonization of A. scholaris ranged from 64 to
91 %. Colonization by five AM fungi increased plant height, diameter, total fresh weight, total dry
weight and total length root. Glomus clarum was more effective in improving nutrient content and plant
growth of A. scholaris than G. decipiens, Entrophospora sp., Glomus sp. ZEA and Glomus sp. ACA. Total
root length of A. scholaris ranged from 1,180 to 1,310 cm. The results suggest that AM fungi can
accelerate the establishment of the seedling stocks of A. scholaris. This finding would contribute to the
effort of establishing A. scholaris plantation.
Keywords: Glomus sp., Gigaspora decipiens, Entrophospora sp., native mycorrhizal fungi, growth
promotion, seedlings, greenhouse.
I. INTRODUCTION
The Apocynaceae family is important as they provide valuable timber (Turner, 2001). It
consists of 164 genera, and some of these genera, i.e. Tabernaemontana, Secamone, Ochrosia,
Dyera, and Alstonia produce timber and nontimber forest products (NTFPs). The genera of
Alstonia consists of 40 species, with A. angustiloba, A. angustifolia, A. macrophylla, A.
pneumatophora and A. scholaris producing milkwood (Soerianegara and Lemmens, 1994). A.
scholaris is a medium-sized to large tree, which can grow up to 35 m in height. Species of A.
scholaris is common in both primary and secondary lowland evergreen to deciduous rain forest
1
2
3
Forest and Nature Conservation Research and Development Center, Jl. Gunung Batu No. 5 Bogor, Indonesia
Corresponding author. E-mail: [email protected]
Faculty of Agriculture, Yamagata University, Tsuruoka 997-8555, Japan
61
Journal of Forestry Research Vol. 4 No. 2, July 2007: 61 - 71
of South Asia, Southeast Asia, Southern China and Northern Australia. Natural regeneration
of A. scholaris occurs preferentially in open areas at forest edges and in secondary forest, and is
considered to be a light-demanding species. Milkwood is suitable for boxes, pencils, crates,
coffins, matches, drawing boards, and furniture components. Moreover, valuable latex is also
harvested from the stem of A. scholaris. The latex can be used for cleaning wounds, traditional
medicine and a good-quality chewing gum. In Southeast Asia A. scholaris is a popular
medicinal plant. Its root bark is known for its antimalarial properties (Macabeo et al., 2005)
and anticancer (Jagetia and Baliga, 2004). However, natural regeneration of A. scholaris is
scarce, and seedlings found scattered or in groups, making it difficult to produce milkwood.
Deforestation rates on the Indonesian islands of Sumatra and Kalimantan are
categorized the highest in the world (Linkie et al., 2004). It is necessary to accelerate
reforestation and afforestation in degraded tropical forests and to enhance the commercial
value of timber, pulp and NTFPs. A. scholaris is among species that, for its value, should be
used in both rehabilitating logged over forest and development of plantation forests. The fast
production of high quality seedling stocks in nurseries is valuable for replenishing degraded
tropical forests. Furthermore, a lot of soils of tropical forests are infertile and the majority of
Indonesian soils are ultisols, which are acid soils. Acid soils are severe environments for
plants; high concentrations of Al, Mn and H, and low availability of N, P, K, Ca, and Mg will
decrease the chance for many tree species to establish and survive (Postma et al., 2007).
Some studies on the effects of arbuscular mycorrhizal (AM) colonization on plant
growth of some tropical trees have been well documented. Arbuscular mycorrhizal fungi
increased plant growth of tropical fruit tree species of Parkia biglobosa, Tamarindus indica, and
Zizyphus mauritiana at after inoculation (Guisso et al., 1998), Tectona grandis (Rajan et al., 2000),
Azadirachta indica (Muthukumar et al., 2001) , and Araucaria angustifolia (Zandavalli et al.,
2004). However, little is known about AM inoculation on growth of Apocynaceae species in
tropical forests. Turjaman et al. (2006) reported that AM fungi increased growth of Dyera
polyphylla seedlings, Guadarrama et al. (2004) reported that AM fungi increased growth of
Stemmadenia donnell-smithii, Weber et al. (1995) reported that AM fungi increased growth of
Adenium obesum, Pachypodium lamerei and Plumeria obtuse. Nevertheless, to the best of our
knowledge, there are no reports on the effect of the growth of Alstonia tree species following
AM fungal inoculation. The objective of this study was to determine whether five AM fungi,
Glomus clarum Nicholson & Schenk, Gigaspora decipiens Hall & Abbott, Glomus sp. ACA Tulasne
& Tulasne, Entrophospora sp. Ames & Scheneider, and Glomus sp. ZEA Tulasne & Tulasne
increase early growth of A. scholaris under greenhouse conditions. Isolates of the five AM
fungi are native to the peat swamp forests of Central Kalimantan.
II. MATERIALS AND METHODS
A. Seed preparation
Seeds of A. scholaris were collected from the arboretum of the Forest and Nature
Conservation Research and Development Center (FNCRDC), Bogor, West Java. The seeds
were soaked in water for two hours and then surface-sterilized by shaking in 5% NaClO
solution for 5 min. They were then thoroughly rinsed twice in sterile distilled water. The seeds
62
Arbuscular Mycorrhizal Fungi ..… M. Turjaman, E. Santoso, and K. Tawaraya
were sown in a plastic flat containing autoclave-sterilized zeolite and grown under a 55%
shading intensity net to control solar radiation. The seeds were allowed to germinate for 21
days after sowing.
B. Soil medium preparation
Soil used in the experiment was an ultisol collected from the Haurbentes Experimental
Forest, Jasinga, West Java (6° 32'-33' S, 108° 26' E) and stored in a greenhouse. It was passed
through a five mm sieve and then mixed with river sand (3:1, v/v) to improve drainage. The
pH (H2O) of the soil mixture was 4.8, available P (Bray-1) was 0.17 mg kg-1, and total N
(Kjeldahl) was 1.7 mg kg-1. The soil mixture was sterilized at 121oC for 30 minutes.
Polyethylene pots (15 x 10 cm2) were filled with 500 g of sterilized soil mixture.
C. Arbuscular mycorrhizal fungal inoculum preparation
Five AM fungi G. clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp. and Glomus sp.
ZEA were isolated from peat soil of Kalampangan, Palangkaraya, Central Kalimantan by trap
culture. The pot cultures began as single spore cultures. They were propagated in pot cultures
of Pueraria javanica. Plastic pots were filled with 175 g of sterilized zeolite and five g of AM
fungal inoculum in the planting hole. Plastic pots were hung in iron racks (1.5x1x1.5m3)
under greenhouse floor and they were made a distance 15 cm between pot cultures to avoid
contamination. The AM fungi in culture pots were checked as determined by morphological
features every two weeks (for three months). A microbial filtrate was not applied to the
controls to account for differences from other fungi or bacteria. A preliminary experiment
showed that AM fungal inoculum was pure culture and effective without a microbial filtrate
application. Two 6-day-old P. javanica seedlings were transplanted into the pots and grown
under natural light greenhouse conditions with no temperature and humidity control. After
90 days, spores, external hyphae, and colonized roots of G. clarum, G. decipiens, Glomus sp.
ACA, Entrophospora sp. and Glomus sp. ZEA were observed in the zeolite.
D. Plants inoculation
One 21-day-old A. scholaris seedling was transplanted into the pots containing sterilized
soil mixture medium. The AM inoculation was achieved by placing five gram of inoculum of
each species 1-3 cm below seedlings. Control seedlings were not mock-inoculated because a
preliminary experiment showed that the sterilized inoculum did not affect growth of the
seedlings. Seedlings were watered daily with tap water to field capacity. No fertilizer was
applied during the course of the experiment. Weeds and pests were removed manually. The
seedlings were grown for five months in a greenhouse at the Forest and Nature Conservation
Research and Development Center, Bogor, West Java (6° 36' S, 106° 45' E). Temperature
varied from 26 to 35oC, relative humidity was 80-90% and the photoperiod was about 12 h.
E. Experimental design
The experiment consisted of six treatments of A. scholaris seedlings (a) control (no
inoculation), (b) inoculation with G. clarum, (c) inoculation with G. decipiens, (c) inoculation
with G. decipiens; (d) inoculation with Glomus sp. ACA; (e) inoculation with Entrophospora sp.;
63
Journal of Forestry Research Vol. 4 No. 2, July 2007: 61 - 71
(f) inoculation with Glomus sp. ZEA. There were ten replications per treatment. Shoot height
and stem diameter at one cm from the soil surface were measured five months after
transplantation. After harvest, shoots and roots were separated. They were oven-dried at 70o
C for 72 h before weighing. Ground shoots were digested with H2SO4 and H2O2 solution (3:1,
v/v). N and P concentration in the digested solution were determined by the semi-micro
Kjeldahl method and vanadomolybdate-yellow assay (Olsen and Sommers, 1982),
respectively. K, Ca and Mg were determined by means of an atomic absorption
spectrophotometer (Heffernan, 1985). An additional 30 seedlings each of A. scholaris
uninoculated or inoculated with G. clarum or G. decipiens or Glomus sp. ACA or Entrophospora sp.
or Glomus sp. ZEA were grown under the same conditions as those of the seedlings in the
above experiment. Numbers of viable seedlings were counted 5 months after transplanting.
Survival rate was calculated as follows:
Survival rate (%) = (number of viable seedlings/number of initial seedlings) x 100
Roots of A. scholaris were washed gently over a two mm sieve under running tap water to
separate them from soil particles. The roots were cleared in 100 g l-1 KOH for 1 h, acidified
with diluted HCl and stained with 500 mg l-1 trypan blue in lactoglycerol (Brundrett et al.,
1996). Roots were destained with 50% glycerol and 30 1-cm segments were viewed under a
compound microscope at x200 magnification. Percentage of AM colonization was estimated
using the gridline intersect method (Giovannetti and Mosse, 1980). Mycorrhizal
dependency (MD) was calculated according to Plenchette et al. (1983): MD (%) = (dry weight
of mycorrhizal plant-dry weight of non mycorrhizal plant) /dry weight of mycorrhizal plant
x 100. Root length were measured by gridline millimeter block.
Data were statistically analyzed using analysis of variance with the statistical software
StatView 5.0 (Abacus Concepts). Comparison of means was done using the least significant
difference (LSD) method at the 5% probability level where the F-value was significant.
III. RESULTS AND DISCUSSION
The roots of A. scholaris were colonized by G. clarum, G. decipiens, Glomus sp. ACA,
Entrophospora sp. and Glomus sp. ZEA 150 months after transplantation under greenhouse
conditions (Table 1.). There was no difference in percentage of colonization among G.
clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp. and Glomus sp. ZEA. The control
seedlings of A. scholaris were colonized by indigenous AM fungi. AM colonization by G.
clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp. and Glomus sp. ZEA increased plant
height, stem diameter, total fresh and dry weight of A. scholaris 5 months after transplantation
(Table 1.) and ready for planting in the field.
64
Arbuscular Mycorrhizal Fungi ..… M. Turjaman, E. Santoso, and K. Tawaraya
Table 1. Arbuscular mycorrhizal (AM) colonization, shoot and root growth of A. scholaris
inoculated with or without AM fungi
Plant growth
AM
Colonization
(%)*
Height
(cm)*
Stem
diameter
(mm)*
Total fresh
weight
(g/plant)*
Total dry
weight
(g/plant)*
No inoculation
16.1a
3.9a
5.3a
1.1a
5a
G. clarum
33.1b
6.5b
20.6b
5.6b
64b
G. decipiens
34.1b
6.9b
18.7b
5.1b
79b
Glomus sp. ACA
32.8b
6.8b
19.7b
5.2b
74b
Entrophospora sp.
36.1b
6.6b
19.2b
4.9b
79b
Glomussp. ZEA
32.5b
6.5b
20.3b
5.0b
91b
Treatment
*Values with the same letter are not significantly different (P
GROWTH AND NUTRIENT CONCENTRATIONS OF MILKWOOD
TROPICAL TREE SPECIES Alstonia scholaris UNDER GREENHOUSE
CONDITIONS
Maman Turjaman1, 2, Erdy Santoso1 and Keitaro Tawaraya3
ABSTRACT
The objective of this study was to determine the effect of five arbuscular mycorrhizal (AM) fungi
on the early growth of Alstonia scholaris (milkwood) seedlings. The seedlings were inoculated with
Glomus clarum Nicholson & Schenk, Gigaspora decipiens Hall & Abbott, Glomus sp. ACA Tulasne &
Tulasne, Entrophospora sp. Ames & Scheneider, and Glomus sp. ZEA Tulasne & Tulasne, and
uninoculated (control) under greenhouse conditions. Percentage of AM colonization, plant growth,
survival rate, mycorrhizal dependency (MD), shoot nitrogen (N), phosphorus (P), potassium (K),
calcium (Ca), and magnesium (Mg) concentrations were measured after 150 days. Survival rates were
higher in the AM-colonized seedlings at 150 days after transplantation than those in the control
seedlings. Mycorrhizal Dependency (MD) values were 80, 78, 79, 78 and 78% in A. scholaris inoculated
with G. clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp., and Glomus sp. ZEA, respectively. Shoot
N, P, K, Ca and Mg content of the seedlings were increased by AM fungi as much as 82-86, 81-86, 81-86,
88-91 and 85-90%, respectively. The percentage of AM colonization of A. scholaris ranged from 64 to
91 %. Colonization by five AM fungi increased plant height, diameter, total fresh weight, total dry
weight and total length root. Glomus clarum was more effective in improving nutrient content and plant
growth of A. scholaris than G. decipiens, Entrophospora sp., Glomus sp. ZEA and Glomus sp. ACA. Total
root length of A. scholaris ranged from 1,180 to 1,310 cm. The results suggest that AM fungi can
accelerate the establishment of the seedling stocks of A. scholaris. This finding would contribute to the
effort of establishing A. scholaris plantation.
Keywords: Glomus sp., Gigaspora decipiens, Entrophospora sp., native mycorrhizal fungi, growth
promotion, seedlings, greenhouse.
I. INTRODUCTION
The Apocynaceae family is important as they provide valuable timber (Turner, 2001). It
consists of 164 genera, and some of these genera, i.e. Tabernaemontana, Secamone, Ochrosia,
Dyera, and Alstonia produce timber and nontimber forest products (NTFPs). The genera of
Alstonia consists of 40 species, with A. angustiloba, A. angustifolia, A. macrophylla, A.
pneumatophora and A. scholaris producing milkwood (Soerianegara and Lemmens, 1994). A.
scholaris is a medium-sized to large tree, which can grow up to 35 m in height. Species of A.
scholaris is common in both primary and secondary lowland evergreen to deciduous rain forest
1
2
3
Forest and Nature Conservation Research and Development Center, Jl. Gunung Batu No. 5 Bogor, Indonesia
Corresponding author. E-mail: [email protected]
Faculty of Agriculture, Yamagata University, Tsuruoka 997-8555, Japan
61
Journal of Forestry Research Vol. 4 No. 2, July 2007: 61 - 71
of South Asia, Southeast Asia, Southern China and Northern Australia. Natural regeneration
of A. scholaris occurs preferentially in open areas at forest edges and in secondary forest, and is
considered to be a light-demanding species. Milkwood is suitable for boxes, pencils, crates,
coffins, matches, drawing boards, and furniture components. Moreover, valuable latex is also
harvested from the stem of A. scholaris. The latex can be used for cleaning wounds, traditional
medicine and a good-quality chewing gum. In Southeast Asia A. scholaris is a popular
medicinal plant. Its root bark is known for its antimalarial properties (Macabeo et al., 2005)
and anticancer (Jagetia and Baliga, 2004). However, natural regeneration of A. scholaris is
scarce, and seedlings found scattered or in groups, making it difficult to produce milkwood.
Deforestation rates on the Indonesian islands of Sumatra and Kalimantan are
categorized the highest in the world (Linkie et al., 2004). It is necessary to accelerate
reforestation and afforestation in degraded tropical forests and to enhance the commercial
value of timber, pulp and NTFPs. A. scholaris is among species that, for its value, should be
used in both rehabilitating logged over forest and development of plantation forests. The fast
production of high quality seedling stocks in nurseries is valuable for replenishing degraded
tropical forests. Furthermore, a lot of soils of tropical forests are infertile and the majority of
Indonesian soils are ultisols, which are acid soils. Acid soils are severe environments for
plants; high concentrations of Al, Mn and H, and low availability of N, P, K, Ca, and Mg will
decrease the chance for many tree species to establish and survive (Postma et al., 2007).
Some studies on the effects of arbuscular mycorrhizal (AM) colonization on plant
growth of some tropical trees have been well documented. Arbuscular mycorrhizal fungi
increased plant growth of tropical fruit tree species of Parkia biglobosa, Tamarindus indica, and
Zizyphus mauritiana at after inoculation (Guisso et al., 1998), Tectona grandis (Rajan et al., 2000),
Azadirachta indica (Muthukumar et al., 2001) , and Araucaria angustifolia (Zandavalli et al.,
2004). However, little is known about AM inoculation on growth of Apocynaceae species in
tropical forests. Turjaman et al. (2006) reported that AM fungi increased growth of Dyera
polyphylla seedlings, Guadarrama et al. (2004) reported that AM fungi increased growth of
Stemmadenia donnell-smithii, Weber et al. (1995) reported that AM fungi increased growth of
Adenium obesum, Pachypodium lamerei and Plumeria obtuse. Nevertheless, to the best of our
knowledge, there are no reports on the effect of the growth of Alstonia tree species following
AM fungal inoculation. The objective of this study was to determine whether five AM fungi,
Glomus clarum Nicholson & Schenk, Gigaspora decipiens Hall & Abbott, Glomus sp. ACA Tulasne
& Tulasne, Entrophospora sp. Ames & Scheneider, and Glomus sp. ZEA Tulasne & Tulasne
increase early growth of A. scholaris under greenhouse conditions. Isolates of the five AM
fungi are native to the peat swamp forests of Central Kalimantan.
II. MATERIALS AND METHODS
A. Seed preparation
Seeds of A. scholaris were collected from the arboretum of the Forest and Nature
Conservation Research and Development Center (FNCRDC), Bogor, West Java. The seeds
were soaked in water for two hours and then surface-sterilized by shaking in 5% NaClO
solution for 5 min. They were then thoroughly rinsed twice in sterile distilled water. The seeds
62
Arbuscular Mycorrhizal Fungi ..… M. Turjaman, E. Santoso, and K. Tawaraya
were sown in a plastic flat containing autoclave-sterilized zeolite and grown under a 55%
shading intensity net to control solar radiation. The seeds were allowed to germinate for 21
days after sowing.
B. Soil medium preparation
Soil used in the experiment was an ultisol collected from the Haurbentes Experimental
Forest, Jasinga, West Java (6° 32'-33' S, 108° 26' E) and stored in a greenhouse. It was passed
through a five mm sieve and then mixed with river sand (3:1, v/v) to improve drainage. The
pH (H2O) of the soil mixture was 4.8, available P (Bray-1) was 0.17 mg kg-1, and total N
(Kjeldahl) was 1.7 mg kg-1. The soil mixture was sterilized at 121oC for 30 minutes.
Polyethylene pots (15 x 10 cm2) were filled with 500 g of sterilized soil mixture.
C. Arbuscular mycorrhizal fungal inoculum preparation
Five AM fungi G. clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp. and Glomus sp.
ZEA were isolated from peat soil of Kalampangan, Palangkaraya, Central Kalimantan by trap
culture. The pot cultures began as single spore cultures. They were propagated in pot cultures
of Pueraria javanica. Plastic pots were filled with 175 g of sterilized zeolite and five g of AM
fungal inoculum in the planting hole. Plastic pots were hung in iron racks (1.5x1x1.5m3)
under greenhouse floor and they were made a distance 15 cm between pot cultures to avoid
contamination. The AM fungi in culture pots were checked as determined by morphological
features every two weeks (for three months). A microbial filtrate was not applied to the
controls to account for differences from other fungi or bacteria. A preliminary experiment
showed that AM fungal inoculum was pure culture and effective without a microbial filtrate
application. Two 6-day-old P. javanica seedlings were transplanted into the pots and grown
under natural light greenhouse conditions with no temperature and humidity control. After
90 days, spores, external hyphae, and colonized roots of G. clarum, G. decipiens, Glomus sp.
ACA, Entrophospora sp. and Glomus sp. ZEA were observed in the zeolite.
D. Plants inoculation
One 21-day-old A. scholaris seedling was transplanted into the pots containing sterilized
soil mixture medium. The AM inoculation was achieved by placing five gram of inoculum of
each species 1-3 cm below seedlings. Control seedlings were not mock-inoculated because a
preliminary experiment showed that the sterilized inoculum did not affect growth of the
seedlings. Seedlings were watered daily with tap water to field capacity. No fertilizer was
applied during the course of the experiment. Weeds and pests were removed manually. The
seedlings were grown for five months in a greenhouse at the Forest and Nature Conservation
Research and Development Center, Bogor, West Java (6° 36' S, 106° 45' E). Temperature
varied from 26 to 35oC, relative humidity was 80-90% and the photoperiod was about 12 h.
E. Experimental design
The experiment consisted of six treatments of A. scholaris seedlings (a) control (no
inoculation), (b) inoculation with G. clarum, (c) inoculation with G. decipiens, (c) inoculation
with G. decipiens; (d) inoculation with Glomus sp. ACA; (e) inoculation with Entrophospora sp.;
63
Journal of Forestry Research Vol. 4 No. 2, July 2007: 61 - 71
(f) inoculation with Glomus sp. ZEA. There were ten replications per treatment. Shoot height
and stem diameter at one cm from the soil surface were measured five months after
transplantation. After harvest, shoots and roots were separated. They were oven-dried at 70o
C for 72 h before weighing. Ground shoots were digested with H2SO4 and H2O2 solution (3:1,
v/v). N and P concentration in the digested solution were determined by the semi-micro
Kjeldahl method and vanadomolybdate-yellow assay (Olsen and Sommers, 1982),
respectively. K, Ca and Mg were determined by means of an atomic absorption
spectrophotometer (Heffernan, 1985). An additional 30 seedlings each of A. scholaris
uninoculated or inoculated with G. clarum or G. decipiens or Glomus sp. ACA or Entrophospora sp.
or Glomus sp. ZEA were grown under the same conditions as those of the seedlings in the
above experiment. Numbers of viable seedlings were counted 5 months after transplanting.
Survival rate was calculated as follows:
Survival rate (%) = (number of viable seedlings/number of initial seedlings) x 100
Roots of A. scholaris were washed gently over a two mm sieve under running tap water to
separate them from soil particles. The roots were cleared in 100 g l-1 KOH for 1 h, acidified
with diluted HCl and stained with 500 mg l-1 trypan blue in lactoglycerol (Brundrett et al.,
1996). Roots were destained with 50% glycerol and 30 1-cm segments were viewed under a
compound microscope at x200 magnification. Percentage of AM colonization was estimated
using the gridline intersect method (Giovannetti and Mosse, 1980). Mycorrhizal
dependency (MD) was calculated according to Plenchette et al. (1983): MD (%) = (dry weight
of mycorrhizal plant-dry weight of non mycorrhizal plant) /dry weight of mycorrhizal plant
x 100. Root length were measured by gridline millimeter block.
Data were statistically analyzed using analysis of variance with the statistical software
StatView 5.0 (Abacus Concepts). Comparison of means was done using the least significant
difference (LSD) method at the 5% probability level where the F-value was significant.
III. RESULTS AND DISCUSSION
The roots of A. scholaris were colonized by G. clarum, G. decipiens, Glomus sp. ACA,
Entrophospora sp. and Glomus sp. ZEA 150 months after transplantation under greenhouse
conditions (Table 1.). There was no difference in percentage of colonization among G.
clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp. and Glomus sp. ZEA. The control
seedlings of A. scholaris were colonized by indigenous AM fungi. AM colonization by G.
clarum, G. decipiens, Glomus sp. ACA, Entrophospora sp. and Glomus sp. ZEA increased plant
height, stem diameter, total fresh and dry weight of A. scholaris 5 months after transplantation
(Table 1.) and ready for planting in the field.
64
Arbuscular Mycorrhizal Fungi ..… M. Turjaman, E. Santoso, and K. Tawaraya
Table 1. Arbuscular mycorrhizal (AM) colonization, shoot and root growth of A. scholaris
inoculated with or without AM fungi
Plant growth
AM
Colonization
(%)*
Height
(cm)*
Stem
diameter
(mm)*
Total fresh
weight
(g/plant)*
Total dry
weight
(g/plant)*
No inoculation
16.1a
3.9a
5.3a
1.1a
5a
G. clarum
33.1b
6.5b
20.6b
5.6b
64b
G. decipiens
34.1b
6.9b
18.7b
5.1b
79b
Glomus sp. ACA
32.8b
6.8b
19.7b
5.2b
74b
Entrophospora sp.
36.1b
6.6b
19.2b
4.9b
79b
Glomussp. ZEA
32.5b
6.5b
20.3b
5.0b
91b
Treatment
*Values with the same letter are not significantly different (P